To obtain the best outburst prediction index of rock cross-cut coal uncovering slotted by pulsed water jet,the effects of the rigidity coefficient’s measured value and the initial velocity of gas diffusion to the integrative indexes D and K are analyzed based on the dynamic evolution of coal crake field under water jet. Thus the integrative indexes D and K are excluded. A grey relation model of outburst prediction indexes(K1,S and P)from 7 coal mine’ rock cross-cut coal uncovering in Chongqing,Sichuan and Henan is set up. And the grey relation degrees of the 3 prediction indexes to outburst hazard are calculated by using grey relational analysis method. The results show that the outburst hazard can be more accurately reflected by the cuttings desorption index K1 when a cross-cut coal uncovering slotted by pulsed water jet,and it should be considered as the best outburst prediction index.